Removed all of the parts associated with the bottom skin were removed. The spar and ribs were debured as well as the bottom skin. Mating faces were primered. The nose ribs were joined to the spar with the rear rib. #1 rib enlarged to A5 per plans as well as #5 for the tie down ring. On most spars the nose rib rivets went backwards and the rear rib rivets went forwards. The stiffener angles were also attached.